LXR linux/tools/include/linux/bitops.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef _TOOLS_LINUX_BITOPS_H_
   3#define _TOOLS_LINUX_BITOPS_H_
   4
   5#include <asm/types.h>
   6#include <linux/compiler.h>
   7
   8#ifndef __WORDSIZE
   9#define __WORDSIZE (__SIZEOF_LONG__ * 8)
  10#endif
  11
  12#ifndef BITS_PER_LONG
  13# define BITS_PER_LONG __WORDSIZE
  14#endif
  15
  16#define BIT_MASK(nr)            (1UL << ((nr) % BITS_PER_LONG))
  17#define BIT_WORD(nr)            ((nr) / BITS_PER_LONG)
  18#define BITS_PER_BYTE           8
  19#define BITS_TO_LONGS(nr)       DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long))
  20#define BITS_TO_U64(nr)         DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(u64))
  21#define BITS_TO_U32(nr)         DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(u32))
  22#define BITS_TO_BYTES(nr)       DIV_ROUND_UP(nr, BITS_PER_BYTE)
  23
  24extern unsigned int __sw_hweight8(unsigned int w);
  25extern unsigned int __sw_hweight16(unsigned int w);
  26extern unsigned int __sw_hweight32(unsigned int w);
  27extern unsigned long __sw_hweight64(__u64 w);
  28
  29/*
  30 * Include this here because some architectures need generic_ffs/fls in
  31 * scope
  32 *
  33 * XXX: this needs to be asm/bitops.h, when we get to per arch optimizations
  34 */
  35#include <asm-generic/bitops.h>
  36
  37#define for_each_set_bit(bit, addr, size) \
  38        for ((bit) = find_first_bit((addr), (size));            \
  39             (bit) < (size);                                    \
  40             (bit) = find_next_bit((addr), (size), (bit) + 1))
  41
  42#define for_each_clear_bit(bit, addr, size) \
  43        for ((bit) = find_first_zero_bit((addr), (size));       \
  44             (bit) < (size);                                    \
  45             (bit) = find_next_zero_bit((addr), (size), (bit) + 1))
  46
  47/* same as for_each_set_bit() but use bit as value to start with */
  48#define for_each_set_bit_from(bit, addr, size) \
  49        for ((bit) = find_next_bit((addr), (size), (bit));      \
  50             (bit) < (size);                                    \
  51             (bit) = find_next_bit((addr), (size), (bit) + 1))
  52
  53static inline unsigned long hweight_long(unsigned long w)
  54{
  55        return sizeof(w) == 4 ? hweight32(w) : hweight64(w);
  56}
  57
  58static inline unsigned fls_long(unsigned long l)
  59{
  60        if (sizeof(l) == 4)
  61                return fls(l);
  62        return fls64(l);
  63}
  64
  65/**
  66 * rol32 - rotate a 32-bit value left
  67 * @word: value to rotate
  68 * @shift: bits to roll
  69 */
  70static inline __u32 rol32(__u32 word, unsigned int shift)
  71{
  72        return (word << shift) | (word >> ((-shift) & 31));
  73}
  74
  75#endif
  76